4618: Add sleep before stopFactory.py issues second SIGTERM

stopFactory.py sends a SIGTERM to the process group leader, then
immediately checks to see if any processes are left and sends another
TERM if they are. It then sleeps for an interval (default
500 ms) -- and then tries again up to N retries (default 100).

This just inserts a brief 200 ms sleep between the first SIGTERM
and the second.